Spring seat construction



2 Sheets-Sheet 1 6 Zay INVENTOR.

.46 ePJU/Zza G. P. JOHNSON SPRING SEAT CONSTRUCTION Filed April 25, 1946 Sept. 18, 1951 Sept. 1s, 1951 G, R JOHNSON 2,568,071

SPRING SEAT CONSTRUCTION Filed April 25, 1946 2 Sheets-Sheet 2 shifting movement while still permitting free vertical rocking freedom of the supporting bars on the rear rail I2. The point of bearing contact may be at the bottom of the slot IB, or between the horizontal flanges of the T-bar and the adjacent top surfaces `of the rail I2, the latter arrangement being preferred. I wish it to be understood that instead of providing slots I8 in this main supporting member I2, I may use spacing blocks orbrackets which will define spacing shoulders adapted to hold the rear ends of the supporting bar I'I at their proper spaced distances While still permitting rocking movement of these support-bars. Such latter arrangements might be applicable to automobile seats and airplane seats. Attention is directed to the fact that rearward sliding or shifting movement of each supporting bar I1 is limited by the proximity of the downwardly bent portion I'Ic to the front edge of the frame rail I2. As clearly shown in Figure 2,

`each frame bar I'I, or the entire spring seat assembly, can only shift rearwardly a slight distance before the downwardly bent portion I'Ic strikes` the front edge of the frame rail I2.

Similarly, these supporting bars Il, or the entire spring seat assembly, can only shift or slide in a forward direction through a limited distance before the upwardly bent front ends I'Ib strike the upper inner edge of the front rail I I.

The front ends of the fore and aft supporting bars I'I are secured to a transversely extending front attachment bar 2 I, this preferably being accomplished by bending the lateral flanges I1' in a forwardly extending substantially horizontal direction and securing them to the under side of the attachment bar 2| as by the bolts 22, or by rivets or welding. This attachment bar has yieldable support on the top surface of the front frame rail I I through the medium of leaf spring ends 2 Ia which are bent downwardly and inwardly from the ends of said attachment bar 2|, as best shown in Figuresv 3 and 4. A suitable spring temper is given to the end portions of the bar 2|, or to the entire length of the bar, when forming the leaf springs 2|a as integral portions of the bar. If desired, the leaf springs 2|a might be formed as separately tempered sections of stock riveted or bolted to the ends of the bar 2|. The yieldability of these leaf springs isso proportioned as to give the desired resiliency to the front edge portion of the spring seat assembly. The bottom ends of the leaf springs 2|a are preferably left free to slide on the top surface of the chair frame rail although they may be anchored thereto if desired.

Referring now to the top supporting surface of the spring seat unit I5, this preferably consists of a section of wire netting 24. Although different types of netting may be employed, I preferably use netting of the chain link type in which the individual vstrands of wire 2401I extend transversely of the length of the netting (i. e. extend from side to side of the chair frame) and are looped back and forth for linked connection with adjacent strands, such type of netting being illustrated and described in detail in my prior Patent No. 2,155,792, issued April 25, 1939. Such type of netting has a substantial degree of resiliency or elasticity Awithout deformation, particularly in the direction of its length, which, in the present instance would be in the fore and aft direction of the chair. The front edge of this wire netting has a stiffening rod 25 extending through the loops of the front or end strand, the extremities of this rodbeing bent laterally as indicated at 25 to prevent displacement of the rod. A plurality of helical tension springs 26 having hookshaped ends have their rear ends hooked over this stiifening rod 25, preferably at points where the end strand of the wire netting loops over the rod. The front ends of these tension springs are hooked into spaced holes 28 formed along the rear edge of the front attachment bar 2|.

At the rear edge of the section of netting 24, another stiffening rod 25a similar to therod 25 extends through the loops of the end strand of the netting, the ends of this rod being also bent over at 25 similarly to the rod 25. Hooked to the rod 25a is a series of helical tension springs 26a similar to the springs 26 but preferably slightly longer. The rear ends of the springs 25a are hooked into holes 3| punched along the front edge of a transverse attachment bar 32. This rear attachment bar is secured by bolts, pins or rivets 33 to the upper ends of curved leaf springs 34 which extend upwardly from the dropped portions of the fore and aft supporting bars Il. The lower ends of these leaf springs 34 are secured by bolts, pins or rivets 35 to the top surfaces of the bar I'I adjacent to the rear ends of their dropped portions. Said leaf springs 34 are prestressed in tension or flexure so that they tend constantly to move the rear attachment bar 32 in a rearward direction, thereby maintaining the section of wire netting 24 under continuous tension. It will be evident that these leaf springs 34 afford a free floating mounting for the rear attachment bar 32 and the rear edge of the wire netting 24. This free floating support adds very materially to the vertical resiliency of the rear portion of the surface 24. Weight which is brought to bear near the rear portion of the supporting surface of the netting 24 causes the rear attachment bar 32 to be pressed downwardly to a lower lever than the front attachment bar 2|, although some of this weight may also cause some downward movement of the free oating front bar 2 Thus both the rear and front edges of the flexible supporting surface or netting 24 have a vertically movable free floating support or mounting, but the free floating support of the rear edge (25a, 32) is with respect to the movable sub-frame I5, whereas the free floating support of the front edge 25, 2|) is not with respect to the' sub-frame but instead is with respect to the main frame II. Of course, it will be understood that the tension springs 26 and 26a give addtional free floating support of the netting 24 beyond or in addition to that afforded by the leaf springs 2|a and 34. The number of tension springs 26 along the front edge and the number of tension springs 26a along the rear edge may be increased or diminished by adding or subtracting springs to obtain any desired degree of yieldability of the netting 24 relatively to the attachment bars 2| and 32. The rear leaf springs 34 have suincient rigidity of attachment to the supporting bars I'I and to the transverse attachment bar 32 to enable this transverse attachment bar to function as a spacer or restraining member for malntaining the rear ends of the supporting bars II at their proper spacing when the spring seat unit I5 is being shipped or handled preparatory to being placed in a chair frame. It will be seen that this spring seat construction can be literally dropped into place in the chair frame. It is only necessary to bring the rear ends I'Id of the supporting bars I'I into registrationwith the slots -in thezz'ear- :frame 'lrailalgiwvhereupon thezztront leaf sprngs la .IcanJthen beledrnpp'ed down iupnn Lizheltop .nf :the rnnt :frame :rails fll das. .a `rdfwhichitl-1e:assembly.or mountinglof thegispring seat .construct-ionis .c'ompleted. Figuren i1 ha-veshown a fabrccovering fingdotted lines -asxfextendin-g llover.: the lspring seat .unit slicthis fabric covering extending down over the cuter lsideslofithe `chairrframe l., .l2 Land.'1 r3,.aslis con- Iwentional with upholsteredtchairs. lf desired, a lthin padtmay loe interp'osedfloetween .them/'ire metting'kl :and ther'upholsteryA ccnferngcai..v Super- ;posed meer this isthe conventional upper padaor -cushion381.whichmaylbe composed of elt,.:hair, foam .rubber .or :any .other preferred material. lThe i back .of .thephairlislshown as Ihavingoa :rear cushion 39,. also .ot-.any conventional `construction. l

I have shown three support bars SI1 as apreerred number for thefaverage-Widthf-of rzchair. ebutrit-will be understood that -a greaterorlesser inumber-Tof these--bars may be used/particu- `larly for wider or narrower chairs or other `furniture. LThe side edgesof the netting L24zare prefrerably left entirely free. In thisschain link netting, .as described in detail inmy l.prior :Patent ENQ. 2,155,792, I have `found that a greater Adegree of resiliency is obtained, with less likelihoodof :the netting -assuming -a permanent sag, when the side edges of the netting are left free roi# connectionwith the supporting frame 'I Il, so that all 'ot-the load is sustainedin a direction substantiallyV at right angles to Itheastrands K241i, wherer`relation of the strands isfpreierably-such that there is a substantial spacing 4between the-upper zand lower portions ofthefwire loops, which Vai?- ffords a considerablev degree-of rolling freedom between adjacent strands. Consequently the netting can be freely Worked or twisted -linto different planes -without'permanently stretch- 'u ing or distorting the netting. By thus enabling the netting to adapt itself more readilyand-more `4resiliently to a'shifting or unevenly distributed load, the flexibilityvand'comfort-of the spring seat are increasednas pointed out in my prior Patent 2,155,792. The dropped intermediate portions Ila of the sub-frame bars i1 afford ample vertical space `for a large degree of downward fiexure of the Wire netting 24 without striking any portion of the sub-frame.

While I have illustrated and described what I regard to be the preferred` embodiment of my linvention -nevertheless it will be understoodithat such is merel-y exemplary and that `numerous modifications and 'rearrangements may `be-"made ytherein without-departing `from the essence of the invention.

II' claim: f

` 1. In a springseatfor a chair or the like, the combination of a chair frame, a plurality of fore and aft supporting bars adapted to extend from .front to rear of the chair frame, means for Apiv- .otally mounting the rearends Vof said supportingbars `on the rear o'f'said.,chai-iframe, spring '8 -finatingtmounting- 'of l:one=';edge of said-wire netitingonsaid supporting bars. 1

f :2. In -fa spring seat` construction :for .chairs-:the ,icombinationof achairframa.` support bars adapt- .edto .have vtheir rear ends vtiltablysupported on the; rear of said vchair frame .adjacent 7to the .Side edges of :the chair, a ycross member connecting ,the front ends of :said support bars, leazf Aspring means :adapted tocarry said cross ,mem- :ber 'on thefront of the chair frame, :a sectionfof 'wire netting, 'and spring means connecting 2 the vfront and rear edges iof said netting with :said support bars.

f 3. In a spring seat vconstruction'for a chair, the combination ,of a main chair. framehaving front tand rrear members adjacent .the kfront-and rear edges of the chair, a sub-frame comprising a plurality .of substantially parallel .support vbars adaptedto extend fore vand aft of the main frame and With their vrearnends tiltably supported on the rear member of said 'main frame, a frontal;- tachment bar connected to the front ends "of said support bars, leaf spring means adapted'to carry said front attachment bar on the front member of the chair frame, a section of wire netting, .coil springs connecting .the front edge 'of said Wire netting with said front attachment bar, and leaf springs connecting the rear edge of Asaid wire netting with said support bars.

v4. In a spring seat construction for chairs, the combination of a chair frame, a plurality of substantially parallel support bars adapted tol extend fore and aft of the chair Iramewith sthe grear ends thereof '.tiltably :mounted .on 'therear offthe chair frame, a front 4attachmentbar con- ,-necting the front ends of said `support .barsffleaf ,spring means :adaptedto carry said front attach- 4mentbar `on the frontof the Vchair vraniara Lsection of Wire netting, auplurality -of helical ten- .sion springs `'connected betweenrsaid frontd at- Arear attachment barland the rearedge .of said wire netting, Yand l,curved `leaf springs connecting `said rear lattachment bar withzsaid ,supportzbars `5. In a spring lseat constructionifor .chairsror :the like, the combination of a chair frame, afplu- `rali-ty of substantially parallel support'fhars .adapted .to extend fore and aft .of the :chair .fra-mapeach of said support 'bars Vbeing of T- shapedcross section, the rear .ends of -said sup- `.port bars fbeing received in vertical slots .in the rear-.member .of said chair frame, said support `barshaving dropped intermediate. portions. a

iront attachmentbarrsecured to the Vfrontends -Qf;said :support bars, said front attachment ,bar `having downwardly and inwardly curved leaf spring ends adapted to have yieldablemounting `on the `front member of the :chair frame, helical .tensionsprings connected to said front attach- `ment bar, a section of wire netting connected to-said'ihelical tension springs, helical tension .springsgconnected to the rear edge of said-wire netting. a rear attachment bar connected -to .said rear helical tension springs,4 and bowed leaf springs connected between Vska-id rear .attachment .bar and the dropped portions of said fore/and aft support bars.

Y 6'. In aspring seat-construction'for lchairs or the like, the combination of a chair frame having front and rear members adjacent to the front and back edges of the chair, a plurality of substantially parallel support bars adapted to extend fore and aft of the chair frame. each of said support bars being of T-shape'd cross section, the rear endsV of said support bars being -tiltably received in vertical slots in the rear member of said chair framewhereby the front ends of said support bars can rise and fall around the rear member of said chair frame, said support bars having dropped intermediate portions, said dropped intermediate portions being effective to limit any fore and aft shifting movement of said support bars relatively to said chair frame by striking adjacent edges of the front and rear members of said chair frame, a front attachment bar secured to the front ends of said supportV bars, said front attachment bar having .downwardly and inwardly curved leaf spring ends adapted to have yieldable mounting on the front member of the chair frame to afford a yieldable A front edge for the spring seat construction, helicalvtension springs connected to said front attachment bar, a section of wire netting connected to said helical tension springs, said wire netting being of the chain-link type with the strands of said netting extendingv from side to side of the chair frame and interlaced together to provide axes of relative flexing movement eX- tending transversely of said chair frame, helical ,tension springs connected to the rear edge of said wire netting, a rear attachment bar connected to said rear helical tension springs, and bowed leaf springs connected between said rear attachment bar and the dropped portions of said fore and aft support bars.

v 7. As an article of manufacture for use in the main frame of a chair having front and rear frame members adjacent to the front and rear iedges of the chair: a completely assembled spring cushion unit adapted-to be placed in the chair frame as a unit, said spring cushion unit comprising a sub-frame including a plurality of fore and aft supporting bars having bearing members at their rear ends adapted to have points of rockable bearing support on said rear main frame member whereby the front end of said `sub-frame can swing upwardly and downwardly about said points of rockable bearing support, spring means carried by the front end of said sub-frame adapted to bear against said front -main frame member so as to afford a vertically movable free iioating mounting of the front edge of said sub-frame, a section of wire netting extending across said sub-frame establishing a flexible upper supporting surface for said spring `cushion unit, and helical tension springs connecting said Wire netting with said sub-frame.

8. As an article of manufacture for use in the main frame of a chair having front and rear 'frame members adjacent to the front and rear edges of the chair: a completely assembled spring .cushion unit adapted to be placed in the chair frame as a unit, said spring cushion unit comto bear against said front main frame member so as to afford a vertically movablev free floating mounting of the front edge of said subframe, a section of wire netting extending across the top of said sub-frame, helical tension springs connecting said wire' netting with said sub-frame. and leaf spring means connected between said wire netting and said fore and aft supporting bars.

9. As an article of manufacture for use in th main frame of a chair having front and rear frame members adjacent to the front and rear edges of the chair: a completely assembled spring cushion unit adapted to be placed in the chair frame as a unit, said spring cushion unit comprising a sub-frame having bearing members at its rear end adapted to have points of rockable bearing support on said rear main frame member whereby the front end of said sub-frame can swing upwardly and downwardly about,v said points of rockable bearing support, leaf spring means carried by the front end of said sub.- frame adapted to bear against said front main frame member so as to aord a vertically movable free floating mounting of the front edge of said sub-frame, a section of wire netting extending across the top of said sub-frame, helical tension springs connecting one edge of said netting with said sub-frame, and leaf springs connecting the other edge of netting with said sub-frame.

10. As an article of manufacture for use in the main frame of a chair having frontrand rear frame members adjacent to the front and rear edges of the chair: a completely assembled spring cushion unit adapted to be placed in the chair frame as a unit, said spring cushion unit comprising a sub-frame having bearing members at its rear end adapted to have points of rockable bearing support on said rear main frame member whereby the front end of said sub-frame can swing upwardly and downwardly about said points of rockable bearing support, spring means effective between the front portion of said subframe and said main frame so that the front edge of said sub-frame can have a vertically movable oating movement, a exible seat surface extending across said sub-frame, and helical tension springs connected between said flexible seat surface and said sub-frame.

GUSTAVE P. JOHNSON. 'j

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 53,888 Schimming Apr. 10, 1866 108,966 Carl Nov.,8, 1870 126,675 Clark May 14, 1872 534,610 Mafera Feb. 19, 1895 1,138,986 Sisbower et al May 11, 1915 1,147,771 Warner July 27, 1915 2,155,792 Johnson Apr. 25, 1939 FOREIGN PATENTS Number Country Date 261,294 Great Britain Nov. 18, 192,6 372,778 Great Britain May 11, 1932 609,122 Germany Feb. 7, 1935 

